INTRODUCTION: Since muscle injuries trigger inflammatory processes and inflammation generates heat due to increased local metabolism, hence the level of inflammation can be measured by the temperature gradient. OBJECTIVE: To assess the feasibility of application of thermography in the diagnosis of injuries caused by physical training. METHODS: The study was conducted with adolescent athletes of the Paraná Club, Curitiba, Brazil, who were divided into two groups, namely control and experimental. The control group attended a training session of low intensity and the experimental group a high intensity one. First, a thermographic image of the quadriceps of each athlete was acquired before the training session. After the training session, a blood sample was collected to check the level of serum lactate of each athlete. Subsequently, 24 hours after training, an extra blood sample was performed to check the level of serum CK of each athlete. Another individual thermographic image of the quadriceps was acquired at that stage. RESULTS: The correlation between the lactate and CK was positive and statistically significant rho value = 0.661 (p = 0.038). There was no statistically significant correlation between CK values 24 h post-training and the change in temperature (24 h post-training - pre-training) in the muscles evaluated for the control group. There was a statistically significant difference in temperature (24 h post-training - pre-training) (p<0.05) for the three muscles studied only in the experimental group. CONCLUSION: The results of this study suggest the possibility of use of thermographic images, together with creatine kinase, in order to determine the intensity and location of post-training muscle damage, since the previously mentioned biochemical marker cannot determine the anatomic location of the muscle injury.